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ABSTRACT:The objective of this study was to evaluate the biometry and carcass characteristics of finished Santa Inês crossbred sheep grazed on tropical grass pastures during the dry season. The study was carried out at the Grupo de Estudos em Forragicultura (GEFOR/UFRN), in Macaíba -RN, Brazil. Four forage treatments were evaluated: Brachiaria brizantha cvs. Marandu e Piatã, Panicum maximum cvs. Aruana e Massai. The 2.88 ha-area used was divided in two blocks of 1.44 ha; each one was composed of four plots corresponding to each cultivar, and each plot was subdivided into six paddocks with an area of 0.06 ha. The pastures were managed under intermittent stocking with seven days of occupation and 35 days of rest, with variable stocking rate. No significant difference was observed in the biometric measurements evaluated in the animals, except for chest width in which animals kept in Marandu pastures obtained higher values than those in the Aruana cultivar. The lowest values of average daily gain, final weight and weight at slaughter values were observed in the animals kept in Aruana cultivars. Cut weights of the shoulder, the loins, short legs/shanks and ribs were higher in the animals kept in Marandu grass and lower in those kept in the Aruana grass; however, no differences were observed for the yield of the cuts and for the biometric measurements of the carcass. The evaluated pasture cultivars did not modify the finished sheep carcasses, however, the lower forage mass from Aruana grass pastures in the dry season affected animal performance and the sheep carcass composition.

The objective was to evaluate the productive and structural characteristics of tropical grasses and the performance of sheep supplemented during the dry season. The treatments consisted of Marandu, Piatã, Massai and Aruana cultivars managed under intermittent stocking with seven occupation days and 35 d of rest, with a variable stocking rate. The evaluated variables were the forage masses, the morphological components, the chemical composition of the pasture and sheep performance. The forage mass was similar among the cultivars, while the leaf blade mass and percentage were higher in the Massai cultivar. There were differences between the cultivars for the NDF, ADF, ADL and ash contents in the two grazing cycles. The lowest gains per

This study aimed to evaluate the agronomic and structural characteristics of massai grass under grazing by sheep supplemented in the dry season. The treatments were supplements offered to sheep in massai grass pastures: multiple mixture, leucaena hay, gliricidia hay and soybean meal. The pastures were evaluated regarding: canopy height; forage accumulation and mass; accumulation, mass and percentage of morphological constituents; leaf:stem and green mass:dead material ratio; and pre‐ and post‐grazing forage bulk density. Higher pre‐grazing heights were observed (27.4 cm) in pasture occupied by animals supplemented with multiple mixture. No effects of supplement types for forage mass (average of 4426.6 kg ha−1 of dry matter) or of morphological constituents in pre‐grazing were observed; however, a grazing cycle effect was observed for these variables, with decreased forage mass in the order of 20% between the first and fourth pasture cycle. Involvement of dead material in forage mass increased by 45 and 23% in the pre and post‐grazing, respectively, from the first to the third grazing cycle. Using protein supplements in sheep's diet was not able to modify massai grass structure in the dry season. Massai grass is alternative forage for supplemented sheep production systems in pastures during the dry season, supporting grazing in 150 mm rainfall conditions for 6 months.

The ingestive behavior of sheep supplemented with concentrate in Brachiaria brizantha and Panicum maximum pastures were evaluated during the dry season. Twenty four male sheep of ½ Santa Inês x ½ undefined breed genotypes were used. The treatments were four feeds of cultivar grasses: B. brizantha cvs. Marandu and Piatã, P. maximum cvs. Massai and Aruana. The ingestive behavior of the animals was recorded during two periods of 24 hours. The grazing time, rumination, idleness (minutes day-1), bite rate (bites minute-1), and the frequency of the animals activities in relation to defecation, urination and search for water, concentrated and mineral salt were observed. There was interaction between time of the day and evaluated cultivars based on the grazing time and bite rate response. Sheep grazing on marandu-grass showed higher grazing time between 11 am to 4 pm (257 minutes), compared to animals grazing on aruana-grass (217 minutes). The bite rate was higher for sheep on massai-grass between 11 am to 4 pm (34.32 bits minute-1). There was no grass effect for idleness and rumination, which can highlight the similarity of chemistry characterization and high percentage of structural components in evaluated pastures. The structural limitations and feed mass composition in the dry season caused effects on the ingestive behavior of idleness and bite rate of supplemented sheep in Brachiaria and Panicum pastures.